A landscape is "a mosaic of heterogeneous land forms, vegetation types, and land uses" (Urban et al., 1987). Therefore, assemblages of different ecosystems (the physical environments and the species that inhabit them, including humans) create landscapes on Earth. Although there is no standard definition of the size of a landscape, they are usually in the hundred or thousands of square miles.
Species composition and population viability are often affected by the structure of the landscape; for example, the size, shape, and connectivity of individual patches of ecosystems within the landscape (Noss, 1990). Conservation management should be directed at whole landscapes to ensure the survival of species that range widely across different ecosystems (e.g., jaguars, quetzals, species of plants that have widely dispersed pollen and seeds) (Hunter, 2002: 83-85, 268-270).
Diversity within and between landscapes depends on local and regional variations in environmental conditions, as well as the species supported by those environments. Landscape diversity is often incorporated into descriptions "ecoregions,"
- a mosaic of heterogeneous land forms, vegetation types, and land uses (Urban et al., 1987)